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@@ -1,13 +1,28 @@
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_(You may browse this at https://github.com/ocornut/imgui/blob/master/docs/BACKENDS.md or view this file with any Markdown viewer)_
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-## Dear ImGui: Backends
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+# Dear ImGui: Backends
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-### Integrating backends
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+## Index
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+
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+- [Introduction](#introduction)
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+ - [Getting Started](#getting-started)
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+ - [What are Backends?](#what-are-backends)
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+- [Using standard Backends](#using-standard-backends)
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+- [Using third-party Backends](#using-third-party-backends)
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+- [Writing your own Backend](#writing-your-own-backend)
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+ - [Using a custom engine?](#using-a-custom-engine)
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+ - [Platform: Implementing your Platform Backend](#platform-implementing-your-platform-backend)
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+ - [Rendering: Implementing your RenderDrawData function](#rendering-implementing-your-renderdrawdata-function)
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+ - [Rendering: Adding support for `ImGuiBackendFlags_RendererHasTextures` (1.92+)](#rendering-adding-support-for-imguibackendflags_rendererhastextures-192)
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+
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+## Introduction
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+
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+### Getting Started
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💡 The **[Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) wiki guide** has examples of how to integrate Dear ImGui into an existing application.
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<BR> The [EXAMPLES.MD](https://github.com/ocornut/imgui/blob/master/docs/EXAMPLES.md) documentation may also be worth a read.
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-### What are backends?
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+### What are Backends?
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Dear ImGui is highly portable and only requires a few things to run and render, typically:
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@@ -34,13 +49,13 @@ and the backends which we are describing here (backends/ folder).
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- You should be able to write backends for pretty much any platform and any 3D graphics API.
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e.g. you can get creative and use software rendering or render remotely on a different machine.
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-### Standard backends
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+## Using standard Backends
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**The [backends/](https://github.com/ocornut/imgui/blob/master/backends) folder contains backends for popular platforms/graphics API, which you can use in
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your application or engine to easily integrate Dear ImGui.** Each backend is typically self-contained in a pair of files: imgui_impl_XXXX.cpp + imgui_impl_XXXX.h.
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- The 'Platform' backends are in charge of: mouse/keyboard/gamepad inputs, cursor shape, timing, and windowing.<BR>
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- e.g. Windows ([imgui_impl_win32.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_win32.cpp)), GLFW ([imgui_impl_glfw.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_glfw.cpp)), SDL2 ([imgui_impl_sdl2.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_sdl2.cpp)), etc.
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+ e.g. Windows ([imgui_impl_win32.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_win32.cpp)), SDL3 ([imgui_impl_sdl3.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_sdl3.cpp)), GLFW ([imgui_impl_glfw.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_glfw.cpp)), etc.
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- The 'Renderer' backends are in charge of: creating atlas texture, and rendering imgui draw data.<BR>
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e.g. DirectX11 ([imgui_impl_dx11.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_dx11.cpp)), OpenGL/WebGL ([imgui_impl_opengl3.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_opengl3.cpp)), Vulkan ([imgui_impl_vulkan.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_vulkan.cpp)), etc.
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@@ -53,44 +68,41 @@ For example, the [example_win32_directx11](https://github.com/ocornut/imgui/tree
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**Once Dear ImGui is setup and running, run and refer to `ImGui::ShowDemoWindow()` in imgui_demo.cpp for usage of the end-user API.**
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-### List of backends
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+### List of standard Backends
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In the [backends/](https://github.com/ocornut/imgui/blob/master/backends) folder:
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List of Platforms Backends:
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- imgui_impl_android.cpp ; Android native app API
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- imgui_impl_glfw.cpp ; GLFW (Windows, macOS, Linux, etc.) http://www.glfw.org/
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- imgui_impl_osx.mm ; macOS native API (not as feature complete as glfw/sdl backends)
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- imgui_impl_sdl2.cpp ; SDL2 (Windows, macOS, Linux, iOS, Android) https://www.libsdl.org
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- imgui_impl_sdl3.cpp ; SDL3 (Windows, macOS, Linux, iOS, Android) https://www.libsdl.org (*EXPERIMENTAL UNTIL SDL3 IS RELEASED*)
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- imgui_impl_win32.cpp ; Win32 native API (Windows)
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- imgui_impl_glut.cpp ; GLUT/FreeGLUT (this is prehistoric software and absolutely not recommended today!)
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+ imgui_impl_android.cpp ; Android native app API
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+ imgui_impl_glfw.cpp ; GLFW (Windows, macOS, Linux, etc.) http://www.glfw.org/
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+ imgui_impl_osx.mm ; macOS native API (not as feature complete as glfw/sdl backends)
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+ imgui_impl_sdl2.cpp ; SDL2 (Windows, macOS, Linux, iOS, Android) https://www.libsdl.org
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+ imgui_impl_sdl3.cpp ; SDL3 (Windows, macOS, Linux, iOS, Android) https://www.libsdl.org
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+ imgui_impl_win32.cpp ; Win32 native API (Windows)
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+ imgui_impl_glut.cpp ; GLUT/FreeGLUT (this is prehistoric software and absolutely not recommended today!)
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List of Renderer Backends:
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- imgui_impl_dx9.cpp ; DirectX9
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- imgui_impl_dx10.cpp ; DirectX10
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- imgui_impl_dx11.cpp ; DirectX11
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- imgui_impl_dx12.cpp ; DirectX12
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- imgui_impl_metal.mm ; Metal (with ObjC)
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- imgui_impl_opengl2.cpp ; OpenGL 2 (legacy, fixed pipeline <- don't use with modern OpenGL context)
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- imgui_impl_opengl3.cpp ; OpenGL 3/4, OpenGL ES 2, OpenGL ES 3 (modern programmable pipeline)
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+ imgui_impl_dx9.cpp ; DirectX9
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+ imgui_impl_dx10.cpp ; DirectX10
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+ imgui_impl_dx11.cpp ; DirectX11
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+ imgui_impl_dx12.cpp ; DirectX12
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+ imgui_impl_metal.mm ; Metal (ObjC or C++)
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+ imgui_impl_opengl2.cpp ; OpenGL 2 (legacy fixed pipeline. Don't use with modern OpenGL code!)
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+ imgui_impl_opengl3.cpp ; OpenGL 3/4, OpenGL ES 2/3, WebGL
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+ imgui_impl_sdlgpu3.cpp ; SDL_GPU (portable 3D graphics API of SDL3)
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imgui_impl_sdlrenderer2.cpp ; SDL_Renderer (optional component of SDL2 available from SDL 2.0.18+)
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- imgui_impl_sdlrenderer3.cpp ; SDL_Renderer (optional component of SDL3 available from SDL 3.0.0+)
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- imgui_impl_vulkan.cpp ; Vulkan
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- imgui_impl_wgpu.cpp ; WebGPU (web and desktop)
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+ imgui_impl_sdlrenderer3.cpp ; SDL_Renderer (optional component of SDL3. Prefer using SDL_GPU!).
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+ imgui_impl_vulkan.cpp ; Vulkan
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+ imgui_impl_wgpu.cpp ; WebGPU (web + desktop)
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List of high-level Frameworks Backends (combining Platform + Renderer):
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imgui_impl_allegro5.cpp
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Emscripten is also supported!
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-The SDL+GL, GLFW+GL and GLFW+WebGPU examples are all ready to build and run with Emscripten.
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-
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-### Backends for third-party frameworks, graphics API or other languages
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-
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-See https://github.com/ocornut/imgui/wiki/Bindings for the full list (e.g. Adventure Game Studio, Cinder, Cocos2d-x, Game Maker Studio2, Godot, LÖVE+LUA, Magnum, Monogame, Ogre, openFrameworks, OpenSceneGraph, SFML, Sokol, Unity, Unreal Engine and many others).
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+The SDL2+GL, SDL3+GL, GLFW+GL and GLFW+WebGPU examples are all ready to build and run with Emscripten.
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### Recommended Backends
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@@ -98,18 +110,32 @@ If you are not sure which backend to use, the recommended platform/frameworks fo
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|Library |Website |Backend |Note |
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|--------|--------|--------|-----|
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-| GLFW | https://github.com/glfw/glfw | imgui_impl_glfw.cpp | |
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+| SDL3 | https://www.libsdl.org | imgui_impl_sdl3.cpp | Recommended |
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| SDL2 | https://www.libsdl.org | imgui_impl_sdl2.cpp | |
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+| GLFW | https://github.com/glfw/glfw | imgui_impl_glfw.cpp | |
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| Sokol | https://github.com/floooh/sokol | [util/sokol_imgui.h](https://github.com/floooh/sokol/blob/master/util/sokol_imgui.h) | Lower-level than GLFW/SDL |
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+If your application runs on Windows or if you are using multi-viewport, the win32 backend handles some details a little better than other backends.
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+
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+## Using third-party Backends
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+
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+See https://github.com/ocornut/imgui/wiki/Bindings for the full list (e.g. Adventure Game Studio, Cinder, Cocos2d-x, Game Maker Studio2, Godot, LÖVE+LUA, Magnum, Monogame, Ogre, openFrameworks, OpenSceneGraph, SFML, Sokol, Unity, Unreal Engine and many others).
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+
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+## Writing your own Backend
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### Using a custom engine?
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You will likely be tempted to start by rewrite your own backend using your own custom/high-level facilities...<BR>
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Think twice!
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-If you are new to Dear ImGui, first try using the existing backends as-is.
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+TL;DR;
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+- Writing your own Renderer Backend is easy.
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+- Writing your own Platform Backend is harder and you are more likely to introduce bugs.
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+- **It is unlikely you will add value to your project by creating your own backend.**
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+
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+**Consider using the existing backends as-is**.
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You will save lots of time integrating the library.
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+Standard backends are battle-tested and handle subtleties that you are likely to implement incorrectly.
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You can LATER decide to rewrite yourself a custom backend if you really need to.
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In most situations, custom backends have fewer features and more bugs than the standard backends we provide.
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If you want portability, you can use multiple backends and choose between them either at compile time
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@@ -131,16 +157,220 @@ Suggestion: try using a non-portable backend first (e.g. win32 + underlying grap
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your desktop builds working first. This will get you running faster and get your acquainted with
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how Dear ImGui works and is setup. You can then rewrite a custom backend using your own engine API...
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-Generally:
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-It is unlikely you will add value to your project by creating your own backend.
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-
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Also:
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The [multi-viewports feature](https://github.com/ocornut/imgui/wiki/Multi-Viewports) of the 'docking' branch allows
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Dear ImGui windows to be seamlessly detached from the main application window. This is achieved using an
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extra layer to the Platform and Renderer backends, which allows Dear ImGui to communicate platform-specific
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requests such as: "create an additional OS window", "create a render context", "get the OS position of this
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-window" etc. See 'ImGuiPlatformIO' for details.
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+window", but some things are more difficult "find OS window under mouse position BUT with some windows marked as passthrough". See 'ImGuiPlatformIO' for details.
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Supporting the multi-viewports feature correctly using 100% of your own abstractions is more difficult
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than supporting single-viewport.
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If you decide to use unmodified imgui_impl_XXXX.cpp files, you can automatically benefit from
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improvements and fixes related to viewports and platform windows without extra work on your side.
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+
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+### Platform: Implementing your Platform Backend
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+
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+The Platform backends in impl_impl_XXX.cpp files contain many implementations.
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+
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+**In your `ImGui_ImplXXX_Init()` function:**
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+- You can allocate your backend data and use `io.BackendPlatformUserData` to store/retrieve it later.
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+- Set `io.BackendPlatformName` to a name `"imgui_impl_xxxx"` which will be available in e.g. About box.
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+- Set `io.BackendPlatformUserData` to your backend data.
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+- Set `io.BackendFlags` with supported optional features:
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+ - `ImGuiBackendFlags_HasGamepad`: supports gamepad and currently has one connected.
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+ - `ImGuiBackendFlags_HasMouseCursors`: supports honoring GetMouseCursor() value to change the OS cursor shape.
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+ - `ImGuiBackendFlags_HasSetMousePos`: supports io.WantSetMousePos requests to reposition the OS mouse position (only used if io.ConfigNavMoveSetMousePos is set).
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+ - `ImGuiBackendFlags_PlatformHasViewports` supports multiple viewports. (multi-viewports only)
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+ - `ImGuiBackendFlags_HasMouseHoveredViewport` supports calling io.AddMouseViewportEvent() with the viewport under the mouse. IF POSSIBLE, ignore viewports with the ImGuiViewportFlags_NoInputs flag. If this cannot be done, Dear ImGui needs to use a flawed heuristic to find the viewport under mouse position, as it doesn't know about foreign windows. (multi-viewports only)
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+
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+**In your `ImGui_ImplXXX_NewFrame()` function:**
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+- Set `io.DeltaTime` to the time elapsed (in seconds) since last frame.
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+- Set `io.DisplaySize` to your window size.
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+- Set `io.DisplayFrameBufferSize` to your window pixel density (macOS/iOS only).
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+- Update mouse cursor shape is supported.
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+
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+**In your `ImGui_ImplXXX_NewFrame()` function or event handlers:**
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+- **Mouse Support**
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+ - Use `io.AddMousePosEvent()`, `io.AddMouseButtonEvent()`, `io.AddMouseWheelEvent()` to pass mouse events.
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+ - Use `io.AddMouseSourceEvent()` if you are able to distinguish Mouse from TouchScreen from Pen inputs. TouchScreen and Pen inputs requires different logic for some Dear ImGui features.
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+ - Use `io.AddMouseViewportEvent()` to specify which viewport/OS window is being hovered by the mouse. Read instructions carefully as this is not as simple as it seems! (multi-viewports only)
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+- **Keyboard Support**
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+ - Use `io.AddKeyEvent()` to pass key events.
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+ - Use `io.AddInputCharacter()` to pass text/character events.
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+- **Gamepad Support**
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+ - Use `io.AddKeyEvent()` and `io.AddKeyAnalogEvent()` to pass gamepad events, using `ImGuiKey_GamepadXXX` values.
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+- **Miscellaneous**
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+ - Clipboard Support: setup `Platform_GetClipboardTextFn()`, `Platform_SetClipboardTextFn()` handlers in `ImGuiPlatformIO`.
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+ - Open in Shell support: setup `Platform_OpenInShellFn()` handler in `ImGuiPlatformIO`.
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+ - IME Support: setup `Platform_SetImeDataFn()` handler in `ImGuiPlatformIO`.
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+ - Use `io.AddFocusEvent()` to notify when application window gets focused/unfocused.
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+- **Multi-viewport Support**
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+ - Update monitor list if supported.
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+ - Setup all required handlers in `ImGuiPlatformIO` to create/destroy/move/resize/title/focus/etc. windows.
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+
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+### Rendering: Implementing your RenderDrawData function
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+
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+Note: set `ImGuiBackendFlags_RendererHasVtxOffset` to signify your backend can handle rendering with a vertex offset (`ImDrawCmd::VtxOffset` field).
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+Otherwise, rendering will be limited to 64K vertices per window, which may be limiting for advanced plot.
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+As an alternative, you may also use `#define ImDrawIdx unsigned int` in your `imconfig.h` file to support 32-bit indices.
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+
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+```cpp
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+void MyImGuiBackend_RenderDrawData(ImDrawData* draw_data)
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+{
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+ // TODO: Update textures.
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+ // - Most of the times, the list will have 1 element with an OK status, aka nothing to do.
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+ // - This almost always points to ImGui::GetPlatformIO().Textures[] but is part of ImDrawData to allow overriding or disabling texture updates.
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+ if (draw_data->Textures != nullptr)
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+ for (ImTextureData* tex : *draw_data->Textures)
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+ if (tex->Status != ImTextureStatus_OK)
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+ MyImGuiBackend_UpdateTexture(tex);
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+
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+ // TODO: Setup render state:
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+ // - Alpha-blending enabled
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+ // - No backface culling
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+ // - No depth testing, no depth writing
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+ // - Scissor enabled
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+ MyEngineSetupenderState();
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+
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+ // TODO: Setup texture sampling state
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+ // - Sample with bilinear filtering (NOT point/nearest filtering).
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+ // - Use 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines;' to allow point/nearest filtering.
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+
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+ // TODO: Setup viewport covering draw_data->DisplayPos to draw_data->DisplayPos + draw_data->DisplaySize
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+
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+ // TODO: Setup orthographic projection matrix cover draw_data->DisplayPos to draw_data->DisplayPos + draw_data->DisplaySize
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+
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+ // TODO: Setup shader: vertex { float2 pos, float2 uv, u32 color }, fragment shader sample color from 1 texture, multiply by vertex color.
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+
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+ // Render command lists
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+ ImVec2 clip_off = draw_data->DisplayPos;
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+ ImVec2 clip_scale = draw_data->FramebufferScale;
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+ for (int n = 0; n < draw_data->CmdListsCount; n++)
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+ {
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+ const ImDrawList* cmd_list = draw_data->CmdLists[n];
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+ const ImDrawVert* vtx_buffer = cmd_list->VtxBuffer.Data; // vertex buffer generated by Dear ImGui
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+ const ImDrawIdx* idx_buffer = cmd_list->IdxBuffer.Data; // index buffer generated by Dear ImGui
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+ for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
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+ {
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+ const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
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+ if (pcmd->UserCallback)
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+ {
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+ if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
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+ MyEngineSetupenderState();
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+ else
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+ pcmd->UserCallback(cmd_list, pcmd);
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+ }
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+ else
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+ {
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+ // Project scissor/clipping rectangles into framebuffer space
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+ // - Clipping coordinates are provided in imgui coordinates space:
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+ // - For a given viewport, draw_data->DisplayPos == viewport->Pos and draw_data->DisplaySize == viewport->Size
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+ // - In a single viewport application, draw_data->DisplayPos == (0,0) and draw_data->DisplaySize == io.DisplaySize, but always use GetMainViewport()->Pos/Size instead of hardcoding those values.
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+ // - In the interest of supporting multi-viewport applications (see 'docking' branch on github),
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+ // always subtract draw_data->DisplayPos from clipping bounds to convert them to your viewport space.
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+ // - Note that pcmd->ClipRect contains Min+Max bounds. Some graphics API may use Min+Max, other may use Min+Size (size being Max-Min)
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+ ImVec2 clip_min((pcmd->ClipRect.x - clip_off.x) * clip_scale.x, (pcmd->ClipRect.y - clip_off.y) * clip_scale.y);
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+ ImVec2 clip_max((pcmd->ClipRect.z - clip_off.x) * clip_scale.x, (pcmd->ClipRect.w - clip_off.y) * clip_scale.y);
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+ if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
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+ continue;
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+
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+ // We are using scissoring to clip some objects. All low-level graphics API should support it.
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+ // - If your engine doesn't support scissoring yet, you may ignore this at first. You will get some small glitches
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+ // (some elements visible outside their bounds) but you can fix that once everything else works!
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+ MyEngineSetScissor(clip_min.x, clip_min.y, clip_max.x, clip_max.y);
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+
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+ // The texture for the draw call is specified by pcmd->GetTexID().
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+ // The vast majority of draw calls will use the Dear ImGui texture atlas, which value you have set yourself during initialization.
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+ MyEngineBindTexture((MyTexture*)pcmd->GetTexID());
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+
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+ // Render 'pcmd->ElemCount/3' indexed triangles.
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+ // By default the indices ImDrawIdx are 16-bit, you can change them to 32-bit in imconfig.h if your engine doesn't support 16-bit indices.
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+ MyEngineDrawIndexedTriangles(pcmd->ElemCount, sizeof(ImDrawIdx) == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, idx_buffer + pcmd->IdxOffset, vtx_buffer, pcmd->VtxOffset);
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+ }
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+ }
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+ }
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+}
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+```
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+
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+### Rendering: Adding support for `ImGuiBackendFlags_RendererHasTextures` (1.92+)
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+
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+Version [1.92.0](https://github.com/ocornut/imgui/releases/tag/v1.92.0) (June 2025), added texture support in Rendering Backends, which is the backbone for supporting dynamic font scaling among other things.
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+
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+**In order to move forward and take advantage of all new features, support for `ImGuiBackendFlags_RendererHasTextures` will likely be REQUIRED for all backends before June 2026.**
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+
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+**TD;DR: List of commits which added support for `ImGuiBackendFlags_RendererHasTextures` in standard backends:**
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+
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+- Allegro5: [ee8941e](https://github.com/ocornut/imgui/commit/ee8941e) (+35 lines)
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+- DirectX9: [75efba7](https://github.com/ocornut/imgui/commit/75efba7) (+48 lines)
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+- DirectX10: [2d2b1bc](https://github.com/ocornut/imgui/commit/2d2b1bc) (+40 lines)
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+- DirectX11: [372fd27](https://github.com/ocornut/imgui/commit/372fd27) (+40 lines)
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+- DirectX12: [eefe5d5](https://github.com/ocornut/imgui/commit/eefe5d5) (+87 lines)
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+- Metal: [26c017d](https://github.com/ocornut/imgui/commit/26c017d) (+55 lines)
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+- OpenGL Legacy: [0430c55](https://github.com/ocornut/imgui/commit/0430c55) (+25 lines)
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+- OpenGL3/WebGL/ES: [dbb91a5](https://github.com/ocornut/imgui/commit/dbb91a5) (+47 lines)
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+- SDL_Renderer2: [9fa65cd](https://github.com/ocornut/imgui/commit/9fa65cd) (+20 lines)
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+- SDL_Renderer3: [e538883](https://github.com/ocornut/imgui/commit/e538883) (+19 lines)
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+- SDL_GPU: [16fe666](https://github.com/ocornut/imgui/commit/16fe666) (+41 lines)
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+- Vulkan: [abe294b](https://github.com/ocornut/imgui/commit/abe294b) (+33 lines)
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+- WGPU: [571dae9](https://github.com/ocornut/imgui/commit/571dae9) (+30 lines)
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+
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+**Instructions:**
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+
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+- Set `ImGuiBackendFlags_RendererHasTextures` to signify your backend can handle the feature.
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+- During rendering, e.g. in your RenderDrawData function, iterate `ImDrawData->Textures` array and process all textures.
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+- During shutdown, iterate the `ImGui::GetPlatformIO().Textures` and destroy all textures.
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+- (Both arrays are `ImVector<ImTextureData*>`. They are only in different location because: to allow advanced users to perform multi-threaded rendering, we store a pointer to the texture list in ImDrawData, with the aim that multi-threaded rendering users replace it with their own pointer.)
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+
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+Pseudo-code for processing a texture:
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+```cpp
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+if (draw_data->Textures != nullptr)
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+ for (ImTextureData* tex : *draw_data->Textures)
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+ if (tex->Status != ImTextureStatus_OK)
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+ MyImGuiBackend_UpdateTexture(tex);
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+```
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+```cpp
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+void MyImGuiBackend_UpdateTexture(ImTextureData* tex)
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+{
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+ if (tex->Status == ImTextureStatus_WantCreate)
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+ {
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+ // Create texture based on tex->Width, tex->Height.
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+ // - Most backends only support tex->Format == ImTextureFormat_RGBA32.
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+ // - Backends for particularly memory constrainted platforms may support tex->Format == ImTextureFormat_Alpha8.
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+
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+ // Upload all texture pixels
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+ // - Read from our CPU-side copy of the texture and copy to your graphics API.
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+ // - Use tex->Width, tex->Height, tex->GetPixels(), tex->GetPixelsAt(), tex->GetPitch() as needed.
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+
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+ // Store your data, and acknowledge creation.
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+ tex->SetTexID(xxxx); // Specify backend-specific ImTextureID identifier which will be stored in ImDrawCmd.
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+ tex->SetStatus(ImTextureStatus_OK);
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+ tex->BackendUserData = xxxx; // Store more backend data if needed (most backend allocate a small texture to store data in there)
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+ }
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+ if (tex->Status == ImTextureStatus_WantUpdates)
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+ {
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+ // Upload a rectangle of pixels to the existing texture
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+ // - We only ever write to textures regions which have never been used before!
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+ // - Use tex->TexID or tex->BackendUserData to retrieve your stored data.
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+ // - Use tex->UpdateRect.x/y, tex->UpdateRect.w/h to obtain the block position and size.
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+ // - Use tex->Updates[] to obtain individual sub-regions within tex->UpdateRect. Not recommended.
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+ // - Read from our CPU-side copy of the texture and copy to your graphics API.
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+ // - Use tex->Width, tex->Height, tex->GetPixels(), tex->GetPixelsAt(), tex->GetPitch() as needed.
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+
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+ // Acknowledge update
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+ tex->SetStatus(ImTextureStatus_OK);
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+ }
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+ if (tex->Status == ImTextureStatus_WantDestroy && tex->UnusedFrames > 0)
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+ {
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+ // If you use staged rendering and have in-flight renders, changed tex->UnusedFrames > 0 check to higher count as needed e.g. > 2
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+
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+ // Destroy texture
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+ // - Use tex->TexID or tex->BackendUserData to retrieve your stored data.
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+ // - Destroy texture in your graphics API.
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+
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+ // Acknowledge destruction
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+ tex->SetTexID(ImTextureID_Invalid);
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+ tex->SetStatus(ImTextureStatus_Destroyed);
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+ }
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+}
|
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|
+```
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+Refer to "List of commits which added support for `ImGuiBackendFlags_RendererHasTextures` in standard backends" above for concrete examples of this.
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